According to a new study, sperm count and quality did not decrease for healthy men who received the first or second dose of the Pfizer or Moderna COVID-19 vaccines. The findings, published in the Journal of the American Medical Association in June 2021, provide evidence that it is highly unlikely that immunization from these two sources compromises male fertility.

The research only applied to vaccines based on mRNA platforms, which Pfizer and Moderna both used. The Johnson & Johnson and AstraZeneca vaccines are based on different genetic material, so were not part of this study. Still, experts say that all four versions of the Covid vaccine work in a similar manner, so it’s highly likely these results would apply to non-mRNA vaccines, too. 

In conducting the study, researchers collected semen samples before the first shot, and 70 days after a second dose, to test for changes in sperm volume, concentration, motility, and total sperm count. 

Though the findings are positive news, the researchers did acknowledge certain limitations to the study. These include a small sample group of 45 men total; the inclusion of only healthy men between 18 and 50 years old; a short follow-up timeframe; and lack of a control group. In addition, since the vaccines are relatively new, further study will be needed to confirm whether the mRNA vaccines will have long-term effects on male fertility. 

Despite these limitations in the study, the research does offer scientifically backed evidence to counter some persistent social media driven myths that the Covid vaccines cause male infertility or even sterility. 

If you have questions about sperm health, our Donor Coordinators are available to answer your questions. You can reach us at (858) 732-8500 or via email. Or, to apply to be a sperm donor, please begin by completing our online application.  

 

San Diego Sperm Bank